I have the stance. I chose it mainly because it was an affordable true-type coilover setup in the rear, as opposed to the oem type. This allowed my to scrap the oem spring perch and replace with spl.
I can only say good things. The quality was outstanding. They were also REALLY responsive. I didn't initially find the adjustment wrenches in the boxes, and when I called they shipped a new set out THAT DAY. Afterwards I found that they were actually in the box (in one of the plastic bags with one of the coilovers) and returned them, but it was a nice experience with their customer service.
My car is an occasional DD (probably 2 days a week or so), and track car. It's still comfortable enough to drive around, but I had stiffer springs before the stance, so I may be a bit jaded.
As for the 15 vs 30 way: what's the difference really? WHat will 30 options give you that 15 wont, except some additional level of adjustment that you probably couldnt even feel? I'm not a professional or anything, so maybe I'm just not sensitive enough, but I doubt most of us are.
And as for the height adjustment: its a threaded body. The only reason to adjust the perch is for preload.
I haven't had any firsthand experience with the BC, but I have heard a few complaints about rattles/squeaks and what not. That may have been an earlier revision, or just poor installation, etc. I think there are some posts in here if you dig around a bit.
Anyhoo, there's this guy's experience. Hope it helps
